Authentik is a self-hosted, open source identity provider, which I use to controll access to most of my homemade services. It is easy to use and easy to maintain, but setting it up within my go-to container setup wasn’t as easy as I thought. I write this post only to save myself time in the future, if I have to do this again. So, if you you read this and think “oh, thank you Captain Obvious!... more...
There are certain film stocks that are more special than others. One example is Cinestill 800T. It is basically motion picture film that got its remjet layer removed to make it safe for C-41 photo lab processing. Removing the remjet layer gives this film its characteristic look when it comes to artificial lights. You’ll see what I mean as soon as you look at the photos at the bottom of this post.... more...
I recently bough this 1.14‘‘ LCD screen for the RaspberryPi Pico. This screen not only just fits perfectly onto the Rasperry, you literally just put it over all of the pin headers, it also comes with a little analog pad, up, down, left, right, as well as an A and B button. So it is already kind of a very small handheld gaming device. The Game It is really simple, the player, a little green square on the left side of the screen, can move up and down using the analog pad, and shoot lasers using the A button.... more...
We all know the stories of spies placing letters in hidden dead letter boxes during foggy cold november nights to communicate with other spies. Since the year is 2022 now, we will build something like this, but using a RaspberryPi Pico W 2. Basically the Raspberry Pi will act as a WiFi Accesspoint, which you can connect to without the actual need of physical contact with the device. The Raspberry Pi will also run a webserver, which we will use to to read and store messages, for anybody else who knows where the WiFi can be found and also have the password.... more...
Text2Image generators like Dall-E or Midjourney are the new hot dudes, when it comes to generating images just from text inputs and also sparked some serious discussions about certain professions might getting obsolete, like artists and photographers. To be honest, it is extremly impressive what these generators can do, but on the other hand they do not replace a photographer for your weddding. Nevertheless I absolutly see practical applications for Text2Image generators.... more...
Sometimes I need a little visual hint to do things, especially when it comes to little things that I should do on repeat, like dayli or even multiple times per day. I’m not really someone who does a lot of sport, but I love to go bouldering. In my “best times” I went three times every week. A few weeks ago I injured my left leg and since then I was not able to go to the bouldering gym anymore.... more...
In this example we will build a very simple chatbot, which we will train on pre-defined questions and answers. This approach is very simple, but in fact could be used to build a chatbot that allows users to talk about a limited scope. So basically you could use this as a different way for users to search your FAQs or allow users to get information usually found in your service documentation or even your product offerings, opening hours and menu of your restaurant and so on, by simply asking.... more...
In this example we will use the Boston housing price dataset to predict house prices based on several features such as crime rate, local tax property rate and so on. The biggest difference to the previous examples here is that we do not predict fixed classes. This time we predict a continous value. Prequesites This is the third part of my Tensorflow and Keras Sample series. To better understand what is going on here, I highly recommend to read part 1 and part 2 first and then return here to continue.... more...
In the first part of this series we developed a simple binary classification model using Keras' Sequential model class, which is the easiest way of using Keras. Since the Squential model is easy to use, but also limited in what we can do with it, we will use Keras' functional API from now on. That way we can build more complex models for use cases that are not so simple. Allthough in this example we will basically use the functional API to build a model that could also be build using the Sequential model to show how it works on with a very simple example and then use this in upcoming parts of this series to implement more complex usecases.... more...
This is the first of - hopefully - a lot of Tensorflow/Keras tutorials I will write on this blog. In this first - very simple - example I will demonstrate how to use Tensorflow and Keras to train and use a model to predict if an IMDB movie review is positiv or negative. We will use the IMDB dataset for this, prepare the training data, so we can use it to train the model, and finally make predictions on data the model has never seen before.... more...
Since Apple’s M1 chip is a really good choice for maschine learning at home, but the setup of a Tensorflow environment isn’t exactly straight forward, I thought it would make sense to simplify it a little bit and write a short guide on how to do it. What we need and what the finished solution will look like We need an Apple device with a M1, M1 Pro or Max chip and macOS 12.... more...
Ever wanted to build a custom controller, or a have a few buttons which you could map some shortcuts to? Then the RaspberryPi Pico and a few touch buttons are everything you need. The Pico can be used as a HID (Keyboard, Mouse or MediaController) by using Adafruit’s HID library. The only problem here is that you can not use it using Micropython, but if we setup the Pico to run Circutpython we are good to go.... more...
I own a classic Nintendo Gameboy, a device that hit the consumer market 32 years ago. I was born one year before that. Of course a few more years passed until I got a Gameboy myself. I played Super Mario Land, Tetris and later Zelda: Links Awakening and (of course) Pokemon. Then the device was replaced by various other consoles and PCs over the next decades. Two years ago I rediscovered it and somehow, after all these years, I felt the desire to relive that time in which I sat down to play those games.... more...
In this how to I will show how to setup a PostgreSQL server on docker, including how to persist data outside of the container, and also how to run PGAdmin in a container as well. In this example I asume that you’ve already got Docker running on your server, if not, set this up first. Install PostgreSQL By default the PostgreSQL container is configured to save its data to /var/lib/postgresql/data inside of the container.... more...
Most tutorials I’ve found so far are about 3-pin photodiodes. These are meant to recieve digital IR signals from TV remotes or similar devices. The 2-pin diodes can be used to simply meassure the available IR light. So you could use this to build a distance sensor, if you add a IR LED emitter and then meassure the reflected light, or to meassure the IR light emitted by a natural or artificial light source.... more...
The Arduino Nano 33 IoT comes with a built-in 3-axis acceleromteter. This sensor meassures values for x, y and z acceleration between -1 and 1. If we want to know the actual position in which the sensor is, we need to know it’s rotation on two axis, pitch and roll, in dregress. This two angles could be used then later on to control two servos which rotate an object exactly the same way the sensor is rotated.... more...
I’m running the official Ubuntu for RaspberryPi on a RaspberryPi 4 and wanted to use the RaspberryPi Camera Module. The thing is, this is not as simple as it is on Raspian. So here are the steps you have to perform to use the Camera Module on Ubuntu. Activate Module First of all connect the Camera Module to your RaspberryPi like you always would and boot it up. Next you have to add the magic setting “start_x=1” to your /boot/config.... more...
On a rainy sunday afternoon I found out that the RaspbeeryPi Pico fits perfectly into a 35mm film box if you cut a little hole for the USB port into the lid. Since my box was a semi-transparent white box, I decided to add some LEDs and build a little temperature sensor, that indicates the current temperature range using either a blue, green, orange or red LED. Build I connected the power pin (long side) of each LED to a GPIO port (green = Pin4, blue = Pin5, orange = Pin3, red = Pin2), of course with a 220 ohm resistor in between, and all the short sides to GND.... more...
A few days ago I got two brand new RaspberryPi Pico Boards and so it is time to build something using this new toy. So let’s talk about what it actually is, how to setup a MicroPython development environment and also build a simple example project to make sure everything works as expected. This one is not like the others I won’t go to much into the specs of this board, since you can read them for yourself here, instead I will focus here on two specific things that set’s this Pi appart from others like it.... more...
As I’ve already mentioned in my article about how this website was built, this website get’s updated every night automatically with content I wrote the day before. To do so I use a cronjob and a little script that get’s the latests version of this website from Github, builds it and then uploads it via ftp. Since mirroring a local directory with a remote ftp directory is a pretty common task, I thought it would make sense to write about how I did it.... more...